docs: def interleave_planes(ipixels, apixels, ipsize, apsize):
      """
      Interleave (colour) planes, e.g. RGB + A = RGBA.
  
      Return an array of pixels consisting of the `ipsize` elements of
      data from each pixel in `ipixels` followed by the `apsize` elements
      of data from each pixel in `apixels`.  Conventionally `ipixels`
      and `apixels` are byte arrays so the sizes are bytes, but it
      actually works with any arrays of the same type.  The returned
      array is the same type as the input arrays which should be the
      same type as each other.
      """
      warnings.warn('please use `Merge Planes` class instead',
                    DeprecationWarning)
      newi = MergedPlanes([ipixels], ipsize, [apixels], apsize)
      return next(newi)